Given the overwhelming scientific evidence on climate change, voluntary reduction of greenhouse gas emissions is becoming increasingly important, especially as diplomatic efforts to secure the commitment of United Nations has proven ineffective. Brazil believes its energy matrix is sufficiently renewable and clean. This may be the reason why there aren’t more official efforts to certify reduced emissions due to the use of clean energy sources. Nevertheless, there are financial incentives for using clean energy sources. In order to avoid the misuse of financial incentives, the electricity regulator in Brazil has developed strict supervision methodology. However, there is no data on avoided emissions. Herein we propose a methodology to certify greenhouse gas (GHG) emission reductions using best principles of governance. This methodology is based on official data, calculates the emissions avoided and the equivalent reforestation required to produce the same effect, thus making the results tangible for a less specialized audience. We also describe our practical experience with 120 consuming units that add up to over 1,500 GWh/year.